Ophthalmologic instrument



H. L. DE zENc,

1 OPHTHALMOLOGIC INSTRUMENTA Nav. 24 1925.

Filed Sept. 13, 192] ATTORNEYS HENRY L; DE ZENG, OF TJOltElSTOl/lii', NEW JERSEY, ASSGNOR CEO ZENG STANBARID COMPANY, OF CAMl-JEN, NEW JERSEY, GRPRATIN OF NEW "IERSLEY.

Application led leptemlier To all fur/0m it may concern.:

Bc it hnoun that I, llnNnr L. Dn ZENG, a citizen. et the United States, residing at liloorestown, county ot Burlington, State of New Jersey, haveinvented a new and useful phthalmologic instrument, of Which vthe ilolloiving is a specication.

In some types ot ophthahnoscopes, retino' scopes, etc., now on the lnarlret, the governing; or controllingl of the illuminationisacconqilished by governing` the intensity of 'illumination oi the light source through the use of a variable electrical resistance in series With the light source. Such control of the illumination is satisfactory Within certain limitations, but in tufo important particulars it proves quite inadequate. rthe two particulars in which my in'iproved control ot illun'iination is supe 'ior are firstly in maintaining a clearly delined limit to the arezA illuminated and secondly in providing' either diffused ligrht or light eina- "mating directly from the light source as may he desired.

ln the ophthalmoscope a normal amount 'ot perfectly diffused light is ordinarily the most satisfactory but there are cases in which either more or less illun'iination either dilliused or undiii'used may be highly advant; genus. lu making' examinations oi? persons whose eyes are particularly sensitive to iight, it may be very desirable to use a `ejreatly reduced ilhunination. And again there are instances, such as the presence ot small vitreous opaeities which necessitate a# greatly increased illumination. These variable requirements in illumination are tully met in the present invention.

retinoscope to be most serviceable must be -apalile oi adjusti'i'ient in .illumination to 'meet the different requirements*which present themselves. `liiiused light is preterahle in retinoscopy, but unditi'used light may he cmployei'i. A. very shill'tul .operator Who is kept in tull training.;F by almost daily uselof the retinoscope requires, 'for his utn'iost satisfaction on exceedingly smal] spot of welldiitiussei'l light by which a very quick and :wcurate reflex is obtained as the projected light is made to trarerse its path across the eye under examination. 0n the other hand, a less experienced operator or one whose daily Work requires only an occasional re-V sort to the retinoseope, will require a somewhatlarger spot in the instrument in order UHTHALMOLQGIC INSTRUMENT.

13, 1921. Serial No. 500,403.

that he may be able to see and properly interpret the reflex action obtained. Finally, the average operator who uses a retinoscope, requires 'for his greatest satisfaction in its use, some provision for controlling;` the size of the light spot in his retinoscope so that he is enabled to arrive quickly at an approximate diagnosis by using` the light spot of larger size `following which the use of the smaller light spotenahles him, with careful attention, to arrive `at his final and more yaccurate results. In both `ophthalinoseopy and retinoseopy the state or degree ot ditiusion is important and the present invention covers control of the degree of diffusion as Well as the change from kdiffused to undit- 'fused light or vice versa. All of these eX- actingrequirements are provided for in a very simple and practicable manner in the present invention, which relates to certain novel features of advantage and construction in opthalmologic instruments, such as opthalmoscopes, retinoscopes, etc., and has particular reference to novel means "tor governing the illumination.

A in'incipal object oi' the invention is to provide novel means for obtaining'either direct or diffused light 'from the saine instrument, as required either in opthalrnoscopy or retinoscopy, thereby providiiip,` means tor practicing' either' art With the same instrument. A further important obicct `is to provide means for varying the size ot the opening through which the light passes on its way trom the source to the object.

Other objects of my invention are to provide novel means for changing;` the character ot the illumination and to provide an instrument by the use of which,v the examination ot the eye may be made more accnratef ly under superior` illuminating` conditions than heretofore, also in which the type ot the illumination may be varied.

Further object and advantages ot my improved instrument `ufhia'fh include sin'iplicit-y ot design and construction by which the foregoingresults may be accomplished in a practicable manner, as Will be apparent from the following' specification taken in connection with the accoinpanyinggl dran* ings, in both of Which the preferred forms oilthe invention are 'described hy Way of illustration only, tbut it vvill be understood that' l may male any modiiication in the details ot construction shown anddescrihed Cil lili) fill' within the scope of the appended claims, without departing from or exceeding the spirit of my invention.

Figure l represents a side elevation of an Ophthalmologie instrument embodying my invention.

Figure 2 of Figure l.

Figure 3 represents a section on line 2)-3 of Figure 2.

Figure el represents a perspective view of a slide employed.

Figure 5 represents a section on line 5 5 of Figure fl.

Similar numerals of reference indicate corresponding parts.

Referring to the drawings-h 1 designates my novel construction of Ophthalmologie instrument, the same comprising the handle'Q, Within Which is a storage battery of any conventional type, having the manually operated thumb piece. 3, whereby the electric light st is controlled, its rays passi-ng upwardly through the passage 5 and the lens G, to the reflector 7, all of the foregoing elements as Well as the other elements portrayed in the drawings, being of any conventional type, with the exception of the novel feature of my invention which will now be described and which consists in the provision of the slide S, which comprises the body portion 9 having the ports or openings therein, l0, 11: and l2, Whose diameter increases in the order stated. n

The slide 8 is manually moved or adjusted at a right angle to the longitiulinal axis of the instrument, being guided and' supported in the slots or Ways 13, and one edge of said slide is provided with the notches 14, which are engaged by the nose 15 of the resilient catch or detent 1G, which is secured in position by the screw 17, it being apparent that the notches 1l are so positioned With respect to the openings 10, l1 and 12 that the desired opening, when they slide is locked, is always in alignment withy the longitudinal axis and with the opening` 1S, in proximity to the source of light l.

In the practice of ophthalmoscopy, thc operator will ordinarily move the slide S until the hole 12 Which is the largest and. contains no diffuser, is brought into operative alignment and he will then proceed with his` eye examination. If, however, he finds that for any reason he Wishes a reduced illumination, or Wishes to employ light in a state of diffusion, he Will, then, by means of pressure With one finger, move the slide 8 until the next opening 11, carrying a light diiiuser 19l is brought into alignment. Usually he Will not, in the practice of ophthalmoscopy, require the use of the smallest opening 10.

represents a section on line 2-2- In practicing retinoscopy, the oeralor Will usually move the slide 8 until the hole 11 carrying the light diffuser 1.9 is brought into alignment, thus providing the illumination most generally adapted to the practice of retinoscopy. rlhe most skillful retinoscopists Will, however, move the slide 8 so that the smallest hole 10 carrying the diffuser 2O is brought into alignment, the small spot of diffused light produced thereby bcing ideal for retinoscopic examination. The construction and arrangement of the slide 8 makes possible the adjustment of the slide by simply pressing the finger against it Without removing the instrument from the position 'normal for the making of an eye examination.

In the accompanying drawings, the in vention is shown in its application to the ophthalmoseope. It Will be understood, of course, that the invention applies equally to the ret-inoscope, the head of the retinoscope then being used in place of the ophthalmoscope head. Moreover, the employ ment in the present invention, of a condensing lens 6 between the light source is and the rerliector 7, the focal length of which lens is considerably greater than is customarily employed in ophthalmoscopes, permits the use of the ophthalmoscope in the prac tice of retinoscopy as Well as in the practico of o phthalmoseopy. The great advantage thus obtained in enabling the operator to practice both ophthalmoscopy and retinoscopy with the same instrument will he at once evident.

It will now be apparent that I have devised a novel ophthalmologic instrumen( which enibodies the features of advantage enumerated as desirable in the statement oi' the invention and the above dcscriigition, and While I have in the present instance, shown and described a lincferred embodiment thereof which will give in practice salisfactory and reliable results, it is lo be understood that such emboifliment is susceptible of modification in various lnirticulars williout departing from the spirit or scope ot the .invention or sacrificing any of its advantages.

Having thus described my invention, what I claim as new' and desire lo sei-ure by Letters Patent, is:-

An ophthalmological instrument comprisH ing al source of light, a light passage way extending therefrom, a reflector in line with the light passage way, a slide operative in the passage Way beyond the light source, having three openings, lnogressively increasing in size, one of said oimnings hav ing clear illumination and the other two having a ground glass screen litted respectively therein.

Hnnnr L pn anno. 

